液晶胆甾相中的分子短程关联

向列相液晶的二粒子集团理论被推广应用于研究胆甾相二维模型.手征性分子固定在三维简单立方晶格的格点上,而分子取向限制在二维.理论结果表明,平衡态螺旋波矢依赖于温度的变化,且存在胆甾相到向列相相变.通过考虑分子间短程关联,二粒子集团理论的数值结果较平均场理论更接近Monte Carlo模拟结果.

Short Range Correlations Between Molecules in Cholesteric Phase of Liquid Crystals

The two-particle cluster theory of nematic liquid crystals is generalized to study a two-dimensional model of cholesteric phase. The chiral molecules are placed at the sites of a three-dimensional simple cubic lattice with molecular orientations confined to two dimensions. The theoretical result shows that the helical wave-vector for equilibrium state depends on temperature and the cholesteric-isotropic phase transition exists. The two-particle cluster theory, taking into accout short-range correlations between molecules, yields numerical results which are closer to those of the Monte Carlo simulation than the mean field theory.